Process of making aldehydes



A. A. BACKHAUS AND F.B. ARENTZ.

PROCESS OF MAKING ALDEHYDES.

APPLICATION FILED JUNE 24, I918.

Patented Aug. 30, 1921.

' of Making UNITED- s'r-arlas-v PATENT OFFICE.

ARTHUR A. BAGKHAUS, OF BALTIMORE, AND FRED B. ABENTZ, OF CURTIS BAY,

MARYLAND, ASSIGNOBS IO U. S. INDUSTRIAL OF WEST VIRGINIA.

rnocnss or-mAxmG ALDEHYDES.

Patented Aug. 30, 192 1. Application filed Junev 24, 1918. Serial No.241,649.

To allwlwmtt may deem.-

Be it known that we, ARTHUR A. BACK- land, and FRED B. ARENTZ, of CurtisBay,

in the county of Anne Arundel, and in the.

State of Maryland, have invented a certain new and useful Improvement inProcesses Aldehydes, and do hereby declare that the following is a full,clear, and exact description thereof.

Our invention relates particularly to a process of producing aldehydes,but it has reference particularly to the production of acetaldehyde.

The object of our invention'is to provide a process by means of whichaldeyhdes, and particularly acetaldehyde, may be readily formed from thecorresponding alcohol.

A further object is to carry out saidz'process by means. of a catalyzer.v

Further objects-of our invention will appear from the detaileddescription thereof contained hereinafter.

one form of our process hereinafter, and

while said process is capable of being carried out with many differenttypes of apparatus, for the purpose of illustration we ave shown onlyone type of apparatus. for use in connection therewith in theaccompanying drawing, in which- The figure is a diagrammaticrepresentation, partly 'in section, of an apparatus which maybe-used incarrying out our invention.

In the drawing, we have shown an alcohol still 1, adapted to be heatedby means of a steam jacket 2, havinga vapor outlet pipe 3, which assesthrough a preheater 4, adapted to cheated in any suitable'way, as forexample by an oil jacket 4:, havin inlet and outlet. pipes 4 and 4; Thetu e 3 is connected to a catalyzer 5, which is comprised ofatube 6,carrying a quantity of granular porous-material 6, such for example" aspumice. stone, unglazed porcelain, charcoal or terra cotta, carryingthroughout the same particles of a finely divided catalyzer metal, suchfor example as copper, nickel, chromium,' or iron, which may bedeposited therein by any suitable means, but preferably in sue thereduction of an oxid of the metal by a Specification of Letters Patent.

a manner as to involvecurrent of hydrogen, as for example by'impregnating the carrier with a nitrate of the metal, precipitating withammonia, drying, i niting and reducing with hydrogen; ai catalyzer 5 isprovided with any suitable heating means, but may, for examle, berovided for this purpose with a eating acket 7, having inlet and outletpipes 8 and 9, respectively, for supplyin a current of highly heated oilthereto. tube 10 leads from the upper portion of the catalyzer 5 to acondenser 11, which is provided with the usual inletand outlet pipes forcoolingwater 12 and '13, andwhich is adapted to condense the 'alcoholfrom the vapors which pass out of-the catalyzer 5.

The condensed alcohol is caught in a oy-' nrconor. so, A ooaronurron flindrical receiver 1 1 and maybe drawn'ofi by valved pipe 15, while theuncondensed gases, comprising acetaldehyde and hydrogen, pass out by apipe 16, which may contam a compressor 16*, and thence to a condenser17, adapted to be supplied with cooling water by 111161; and outletpipes 18 and 19. The compressor 16 may be omitted if desired, but, ifomitted, the condenser 17 would be supplied with brine. The. condenser17 condenses the acetaldehyde, which is collected in a cylindricalreceiver 20, having a valved draw-off pipe 20*, while the uncondensedgases, comprising the hydrogen formed in the process, are conveyed offby pipe 21, and may be discharged therefrom through a pressure reliefvalve 22.

In carrying out our process, a quantity of an alcohol, such for exampleas ethyl alcohol, is introduced into the still 1, and is distilledtherein by means of the heat applied by the steam jacket 2. The alcoholvapors are conveyed away by the pipe 3 to the preheater 4, where thevapors are heatedto atemperature of between 250 and 350 (3., butpreferably to approximately 300 0., before they enter the catalyzer'5,the temperature at'which it is desired to act upon the alcohol vapors inthe catalyzer,"

The alcohol vapors, therefore, enter the catalyzer '5 at the requiredtem erature, so

.that the formation of acetalde yde imme-.

diately begins as soon as the vapors reach the finely divided coppercarried upon the granular particles within the catalyzer tube 6. The oiljacket 7 maintains the vapors in the tube at from 250 to 350 C.,-'butpreferably about 300 (1., throughout the entire ing an alcohol vapor toa temperature lying length of said tube, and a large percentage of thealcohol vapors in thus decomposed to form acetaldehyde and hydrogen.

The vapors passing out of the catalyzer by means of the tube 10 areconducted through the condenser 11, maintained at a temperature of 2030C., where any alcohol vapors present are condensed and are collected inthe receiver 14, from which the alcohol may be drawn off by means of thepipe 15. The acetaldehyde and the hydrogen pass out of the receiver 14and are conducted to the compressor 16, where the gases are compressedto approximately 60 pounds per square inch. The compressed gases thenpass through the condenser 17 maintained at a temperature of 1020 (3.,where the acetaldehyde is condensed and collected in the receiver 20. Incase the compressor 16 is not used, the temperature in the condenser 17should be about 0 C.

The hydrogen is conveyed away from the lief valve 22. The hydrogen maybe collected in any suitable manner. In this way the acetaldehyde isreadily and continuously formed from the alcohol vapors formed in thestill 1.

lVhile we have described our invention above in detail, we wish it to beunderstood that many changes may be made therein without departing fromthe spirit of our invention.

We claim:

1. The process which comprises preheatbetween 250 and 350 degrees (1.,and passing 'it through a catalytic agent comprising finely dividedmetallic particles maintained at about the above temperature, andseparating out the aldehyde formed.

2. he process which comprises preheating an alcohol vapor to atemperature lying between 250 and 350 degrees 0., passin the vaporsthrough a catalytic agent comprising finel divided metallic particlesmaintained at a ut the above temperature, and separating the aldehydeformed from the alcohol vapors by fractional condensation.

3. The process which comprises preheating alcohol vapors to atemperature lying between 250 and 350 degrees 0., passing them through aporous catalytic agent containing finely divided metallic particlesmaintained at a temperature substantially as the above temperature andcontained in a non-porous container, and separating the aldehyde formedfrom the alcohol and hydrogen.

4. The process which comprises preheating' ethyl alcohol vapor to atemperature lying between 250 and 350 degrees C., and passing the vaporthrough a catalytic agent comprising finely divided metallic part clesmaintained at about the above temperature, and separating out thealdehyde formed.

In testimony that we claim the foregoing We have hereunto set our hands.

ARTHUR A. BACKHAUS. FRED B. AR-ENTZ.

Witnesses:

JOHN P. GIsoHEL, ARTHUR WRIGHT.

